More than 350 spp. 2-30mm. Antennae 11 segmented, filiform, inserted laterally
between eyes and mandibles, variously setose and pubescent. Tarsi 5-5-5, usually simple although male often
with protarsi dilated basally (but see Demetrias.) Head, thorax and elytra usually with discrete sensory setae. Hind
trochanters are always large and project backwards behind the femurs, a character easily seen even with a card mounted specimen.
A careful count of tarsal segments will eliminate most species likely to be confused with Carabids.
Omaliine Staphylinids, where the elytra almost cover the abdomen and may do so completely in carded specimens, possess
distinct ocelli.Pterostichus madidus (Fab.), very likely to be encountered almost immediately by anybody embarking
upon a study of Coleoptera, is as typical a Carabid as any. Some idea of the range of variation is given below but there also
specialised forms e.g. Omophron, Cicindela and Calosoma.
Found in most situations; arable land and pasture, moors and heaths, many species under bark and logs
in woodland and often huge numbers among waterside vegetation. At least two species, Oodes helopoides and Carabus clathratus
live underwater among vegetation. Pitfall trapping is usually very productive, searching parkland pathways with a torch
on warm spring and summer evenings can reveal large numbers. M.V. light on a vertical sheet and interception nets
often give good results.

For an excellent discussion of Carabid biology and ecology see Forsythe, 2000

Our only species, Omophron limbatum Fab.
(5-6mm) is quite unlike any other carabid; a medium sized yellowish brown beetle with
metallic green markings to pronotum and elytra, almost circular and with the scutellum hidden by the basal margin
of the pronotum. First recorded from Rye harbour, Sussex in 1969 (Farrow, 1971), it is now a very local insect of
flooded gravel pit margins around the Sussex and Kent borders, Norfolk and Suffolk.

Commonly known as Tiger beetles our five species are all of
distinctive appearance; medium sized (9-18mm) metallic species with long slender legs, large eyes and long, toothed mandibles
which are crossed when at rest. Unique among carabids in having the antennae inserted on the upper surface of the head
within the base of the mandibles. Identified by its elongate pronotum, Cylindera germanica L. is a local
coastal species of Dorset, Hampshire and the Isle of Wight. The species rarely flies. Our four species of Cicindela
run fast and fly readily in pursuit of prey. Only C. campestris L. is at all widespread.

Commonly known as Bombardier beetles due to their specialised
defence mechanism; they are able to direct a spray of corrosive liquid and vapour from the abdomen towards a
potential threat. Although charcterised by the number of visible abdominal sternites, seven in the female and
eight in the male as opposed to six in the carabininae, they are readily recognised on general appearance.
Brachinus crepitans (L.) (6-9mm), our only resident species, is light reddish brown but for the dark
metallic blue or green elytra and has the entire upper surface finely pubescent. It is a very local insect of
grassland and open wasteland throughout southern England and southern Wales. Our other species, B.sclopeta (Fab.),
is a very occasional immigrant with recent records (2005) from the London area. It is smaller than crepitans
with the base of the elytral suture broadly red.

Trechini contain six genera of small beetles, mostly less than 6.5mm,
characterised by deep, almost circular furrows on the clypeus around the eyes (Trechus and 'normal' sized last
segment of the maxillary palpi(cf Bembidion). In most species the sutural striae curves back apically onto the eltra. Our two
species of Aepus are tiny beetles, less than 3mm, associated with rocky shores. Perileptus areolatus (Creutzer)
(2.3-2.8mm), distinguished by its small size and pubescent elytra, is a very local species of sandy or shingle river margins.
Blemus discus (Fab.)(4.5-5.5mm) also has pubescent elytra but is much larger, it is a widespread species associated
with moist habitats. Trechoblemus micros (Hbst.)(3.8-4.5mm) has both the eltra and pronotum pubescent again
widespread but local and associated with moist habitats and damp pasture. In Thalassophilus the elytra are bordered basally
while in Trechus the border is abbreviated before the scutellum. Thalassophilus longicornis (Sturm) is a
local and rare species from Wales, northern England and western Scotland, also recorded from Kent. Generally found in
wetland habitats among gravel or fine shingle. Seven species of Trechus occur in Britain of which two, T.obtusus Erichson
and T.quadristriatus (Schrank) are widespread and common.